The invention relates to a reflector supporting apparatus for an astronomical instrument, and more particularly to an apparatus for supporting an aiming and orienting appliance useful in reflector systems.
A reflector supporting device is known from the publication SPIE, vol. 1236, Advanced Technology Optical Telescopes IV (1990) page 86 et seq. In this apparatus two rotationally symmetrical primary mirrors are arranged, as an astronomical instrument, on a common support member at a predetermined spacing. The reflected rays are brought to a common focus by means of deflector mirrors. Multiple reflector mirrors and a protective casing likewise are located on the support member.
The total mass of the support member, the mirrors and the superstructures rests on two pivot bearings of a rotary table which is movable in the horizontal plane. As the pivot bearings are loaded with the full weight of the system, there is a risk that negative effects will occur on the formation of the image, by reason of the inherent vibration and frequency of the optical and mechanical devices during a tilting movement, and which can be restricted only by costly and technically difficult counter measures. In view of the fact that increasing primary mirror diameters, and the additional auxiliary equipment this involves, result in an enormous increase in mass, it is difficult to provide pivot bearings which can accommodate these masses, while observing the required parameters. Accordingly, the known supporting apparatus is little suited for large telescopes in particular, and also for reflector systems having diameters of more than 8 meters, when used in different manner.
Another supporting apparatus of the described type is described in WO 88/06743 by Huegenell. The support member for a reflector telescope in this case is supported hydrostatically by a large bearing surface in a stationary tray, which is adapted to the spherical shape of the support member, so as to be pivotable about the axis of elevation. At two diametrically opposed ends and coaxial with the axis of elevation, the support member includes circular cylinders which are each arranged for rotation in a bushing. The bushings are located in a ring which is disposed concentrically with the tray and is rotatable about the axis of elevation and which also includes a drive.
It is an object of the present invention to provide a supporting apparatus of the kind specified, and wherein the reflectors and deflector mirrors, as well as evaluating means cooperating with them, and which have especially great diameters and masses, can be supported reliably, with non-vignetted image formation, when used as an astronomical instrument, and which also has an undisturbed radiation path at the receiving end and also in the radiation direction.